Hard pastels are very similar to soft pastels. These are available in cylindrical or square sticks, which contain more binder than pigment that is why referred to as hard pastels. Because of hardness they don’t break or crumble easily. The lines created by hard pastels are crisp and prominent hence used for outline and detailing of the pastel drawings.

Hard pastels can solely be used for entire drawing but generally artists prefer to combine it with soft pastels for more subtle effect. They are good for preliminary sketching, small details and finishing touches.

Reference:
http://jackiesimmondsartyfacts.blogspot.in/2012/10/why-use-hard-pastels.html
http://www.art-is-fun.com/pastels.html


Semi Hard Pastels by Mungyo (set of 12) Artists’ grade


"Woman at her toilette" by Edgar Degas using Roche pastels
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